Power loss and excessive smoke

[Castlecom1]

Hello Everyone,

I have a problem with a 2008 Octavia Tdi 8v , it sometimes looses All power (i.e. 50/60mph down to 20/30mph)and will not accelerate, then all of a sudden will throw out a lot of smoke and start accelerating again. It also sometimes 'hiccups' when accelerating. I've changed all filters and oil, but, problem is still there.

It was in regular use as a taxi, but then has been parked up for a few months. Now back in daily use. Problem only started after it had been parked up.

Can Anyone help ?

Zaf

(Newbie from Newcastle)

[Sheldon.Cooper]

VNT mechanism is carbon'd up and needs a really good clean out.

 

Very common on high mileage and/or gently driven TDI engines.

 

Best stuff I've seen (without requiring disassembley of the turbo) is 10K boost.  Just follow the instructions fully then give it an Italian tune up.

[Castlecom1]

Ok thanks will try that. Where can I get it from ?

[Sheldon.Cooper]

Should be freely available on ebay or amazon, possibly from Halfrauds.

 

Just to confirm that's the probable reason for the hesitation you can try moving the VNT linkage yourself and check for excessive resistance.

 

Open the bonnet, find the VNT actuator (look for your turbo, there will be a metal link attaching it to the VNT actuator), on top of the actuator will be vacuum hose.  Using your finger on the bottom of the actuator shaft try moving it up and down, it should move about 1 - 1.5" with only slight resistance.  If it moves too easily then look for a spilt on the vac pipe, if it's a bitch to move then the vacuum will also find it hard to move and that's the problem.

 

The 'real' fix is to remove the turbo and get it fully cleaned internally.... You will need to do this if the 10K boost doesn't work.

 

Too much carbon and nothing but a professional internal clean will shift it.